2. Traffic Classification

This page preserves the original RFC text for the section and adds navigation metadata for the documentation site.

Original RFC Text

2.  Traffic Classification

   The Traffic Classification Data Item represents a list of flows that
   may be used at the same time to provide different service classes for
   traffic sent from a router to a modem.  The data plane information
   used to identify each flow is represented in a separate Sub-Data
   Item.  The Data Item and Sub-Data Item structures are intended to be
   independent of any specific usage of the flow identification, e.g.,
   flow control.  The Sub-Data Item structure is also intended to allow
   for future traffic classification types, e.g., 5-tuple flows.  While
   the structure of the Data Items is extensible, actual flow
   information is expected to be used in an extension-dependent manner.
   Support for DSCP and PCP-based flows is defined via individual Sub-
   Data Items; see below.  Other types of flow identification, e.g.,
   based on IP transport-layer protocol and ports, may be defined in the
   future via new Sub-Data Items.  Note that when extensions supporting
   multiple Sub-Data Item types are negotiated, these types MAY be
   combined in a single Data Item.

   Each list of flows is identified using a "Traffic Classification
   Identifier" or "TID" and is expected to represent a valid combination
   of data plane identifiers that may be used at the same time.  Each
   flow is identified via a "Flow Identifier" or "FID".  Each FID is
   defined in a Sub-Data Item that carries the data plane identifier or
   identifiers used to associate traffic with the flow.  A DLEP
   destination address is also needed to complete traffic classification
   information used in extensions such as flow control.  This
   information is expected to be provided in an extension-specific
   manner.  For example, this address can be provided by a modem when it
   identifies the traffic classification set in a Destination Up Message
   using the Credit Window Association Data Item defined in [RFC9893].
   TID and FID values have modem-local scope.